1. Field of Invention
The present invention relates to a method of protecting AT commands when a terminal device sends AT command to a terminal adapter via serial interface, and more particularly to a method of protecting AT commands when a computer sends AT command to a mobile terminal via serial interface.
2. Description of Related Arts
As a way of communication, a computer sends AT command to a mobile terminal via serial interface to control the mobile terminal through AT command, so as to realize the GSM/UMTS interaction. The user can operate or control the function configuration, call, short message, phonebook, data service, fax, etc. through AT command.
At present, the security of the mobile terminal is getting more and more attention. Security protections are considered in many aspects, but less is considered on AT command. In fact, AT command can not only control GSM related services, such as call services, SMS (Short Message Service), supplementary services and GPRS data services, but also control the functions of mobile terminal, such as operating phonebook, getting IMEI. It's easy for an illegal user to take the control of the mobile terminal without the security protection to the AT commands, which is a hidden trouble.